It is known to place a flap type check valve in the flow stream of a fluid to prevent fluid from flowing in a direction that is opposite to that desired. This type of valve is widely used in such applications as home sump pumps and in industrial chemical plants and in aircraft ground fuel handling equipment. However, in these applications, space is not at a premium and the removal of the fluid duct work that is joined to the check valve assembly is not hindered by the location of other components or surrounding structure. In other applications, the surrounding structure can hinder the removal of the inlet and/or outlet fluid ducts. A good illustration of this type of application is aircraft fluid systems where the back flow of engine generated bleed air cannot be tolerated and where surrounding aircraft structure can be confining for the assembly and disassembly of fluid ducting. In these applications it would be desirable to incorporate a fluid check valve that exhibits a low clearance profile in at least one side of the check valve to allow for the removal of the associated fluid duct with a minimal amount of displacement of the duct away from the check valve. This required amount of displacement would allow the duct to be removed with clearance from the surrounding structure unlike prior art check valves which require that other aircraft systems and structure be disassembled to yield the required amount of displacement clearance to allow for removal of the fluid duct.